It is common practice that files, ratchets and similar tools are manufactured and sold separate from handles for such tools. The file tangs, usually having a triangular configuration, exhibit extreme tolerances even for tools of same type and size. Moreover, it is desired that a handle will be suited for a variety of tool types having different nominal tang dimensions.
In the past, wooden handles were most commonly used. It has also been proposed to use handles made of plastic material, the design of such handles having been quite similar to that of the conventional wooden handles. German utility models Pat. Nos. 72 31 401 and 19 31 900, respectively, disclose such handles. These handles were, however, not successful because of their technical and economical drawbacks.
Technically, the known plastic handles exhibit a tendency to rupture upon the tool tang being driven in because of the extreme radial stresses which occur in particular at the tang bore mouth, the largest dimension of the tang being usually adjacent the very tool body.
Economically, the manufacture of such plastic handles by the conventional injection molding process cannot satisfy. The material being expensive in comparison with wood, the production yield is not competitive either because a relatively great mass of material will need a considerable curing or setting time before a handle may be removed from the mold.
It is the object of the present invention to provide a plastic handle for tools as files or ratchets or the like which may be used for different sizes of tool tangs without the risk of rupture when the tang is driven home, the tool tang remaining nevertheless pressfitted in the handle such that reciprocal forces acting parallel to the tool tang will be transmitted to and from the handle.
In a preferred embodiment of the invention, the handle is provided with indentations extending therein transverse with respect to the tool tang or handle axis, these indentations having the advantage that the mass of handle material is reduced thereby reducing the expenses for the material itself and the time necessary for the material to cure or set in the mold because of the reduced wall thickness.